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Biomedical subjects

M Hiratsuka

Publications and source records attributed to M Hiratsuka.

At least 37 records · Page 2Linked to original sources
PubMed2001

Obliterative airway disease and graft stenting in pig-to-dog tracheal xenotransplantation.

OBJECTIVE: Obliterative airway disease occurring in concordant tracheal xenografts in rodent models is histologically similar to obliterative bronchiolitis in human lung allografts. We studied whether obliterative airway disease would occur in a large animal-discordant model. METHODS: Pig and dog tracheas were cryopreserved for 7 to 14 days, and 18 recipient dogs given splenectomy 7 days before transplantation, then seven tracheal rings were removed and a corresponding five-ring donor tracheal segment was transplanted to the excised site. Grafts were wrapped with pedicled omentum and inmmunosuppression was conducted with tacrolimus or deoxyspergualin. Graft status was observed by bronchoscopy. Dogs were classified into three groups. Group 1 consisted of dog-to-dog allotransplantation animals (control group, n = 5), Group 2 of pig-to-dog xenotransplantation animals (n = 8), and Group 3 of pig-dog xenotransplantation animals who also underwent graft stenting immediately after transplantation (n = 5). RESULTS: Grafts healed well in 4 of 5 Group 1 dogs. Tracheal stricture began on day 5 post transplantation and the lumen was obstructed by fibrosis by days 8 to 14 in all Group 2 dogs. All Group 3 dogs remained in good respiratory status until death. CONCLUSION: Obliterative airway disease developed quickly in pig-to-dog discordant tracheal xenografts. Graft stenting is a feasible treatment for managing of tracheal obstruction.

Airway Obstruction↗
PubMed2001

Application of sentinel node biopsy to gastric cancer surgery.

BACKGROUND: Sentinel node (SN) biopsy has been tried in the management of a variety of cancers with the hope that it would eliminate many unnecessary lymph node dissections, resulting in less morbidity. This important technique, however, has not been tried in gastric cancer surgery. The feasibility of SN biopsy and its accuracy in predicting the lymph node status in patients with gastric cancer were examined in the current study. PATIENTS AND METHODS: SN biopsy was performed in patients with T1 (n = 44) or T2 (n = 30) gastric cancers (ie, immediately after laparotomy, indocyanine green was injected around the primary tumor, and the green-stained nodes [SNs: 2.6 +/- 1.7 nodes per patient] were removed). Then, gastrectomy with extended lymphadenectomy was performed. The unstained nodes (non-SNs: 39 +/- 18 nodes per patient) were obtained from the resected specimens. Both SNs and non-SNs were subjected to histologic examination with hematoxylin-eosin. RESULTS: SNs could be identified in 73 of 74 patients (success rate, 99%). Of these 73 patients, 10 had lymph node metastases in SNs or non-SNs, or both; 6 in both SNs and non-SNs; 3 in SNs alone; and 1 in non-SNs alone. The sensitivity of the SN status in the diagnosis of the lymph node status of the patient was 90% (9/10) and specificity was 100% (63/63). Sensitivity was 100% in the T1 group (n = 44) and 88% in the T2 group (n = 29). CONCLUSIONS: SN biopsy using indocyanine green can be performed with a high success rate, and the SN status can predict the lymph node status with a high degree of accuracy, especially in patients with T1 gastric cancer.

Coloring Agents↗
PubMed2001

Does pleural lavage cytology before thoracic closure predict both patient's prognosis and site of cancer recurrence after resection of esophageal cancer?

BACKGROUND: Operative manipulation occasionally exfoliates and spreads cancer cells in the surgical field, and it is a matter of concern whether the exfoliated cancer cells actually affect the patient's prognosis and sites of cancer recurrence. METHODS: In 240 patients with esophageal cancers, lavage cytology (LC) of the right pleural cavity was performed before and after esophageal resection combined with regional lymphadenectomy. The cytologic results were compared with the pathologic factors associated with cancer extension, postoperative survival, and cause of surgical failure. RESULTS: Only 3 patients (1.3%) were LC positive before resection. Of the 237 LC-negative patients, LC was also negative after resection in 215 patients (90.7%) (LC-/-), but LC became positive after resection in 22 patients (9.3%) (LC-/+). The 3-year survival rate was 0% in the LC-/+ group versus 65% in the LC-/- group, and the median survival rates were 10.9 months and 25.0 months, respectively (P <.0001). Multivariate analysis revealed that LC-/+ was an independent prognostic factor (P =.0331), along with nodal involvement and depth of cancer invasion. However, there were no significant differences in the sites of cancer recurrence between the 2 groups. Only 1 patient was found to develop the first recurrence in the pleural cavity. The LC-/+ group had a higher incidence of bulky lymph-node metastasis (P =.0009). CONCLUSIONS: Pleural LC after resection of esophageal cancer seems to be a prognostic indicator of overall recurrence, but not necessarily in the pleural cavity. Patients with a positive LC after resection may benefit most by effective systemic adjuvant chemotherapy.

Adult↗
PubMed2001

Human stomach-specific gene, CA11, is down-regulated in gastric cancer.

To reveal the implication in gastric cancer pathogenesis of the novel human gene referred to as CA11, which was recently isolated by a differential display technique using normal gastric mucosa and gastric cancer tissue, we examined CA11 expression in 50 primary gastric cancers and also introduced the CA11 gene into gastric cancer cells. RNA dot blot analysis against various human organs and developmental stages demonstrated that CA11 was intensively expressed especially in normal stomach tissue. Northern blot analysis showed that expression of the CA11 gene in cancer tissue was down-regulated compared with normal tissue. Semi-quantitative RT-PCR also demonstrated that CA11 gene expression was decreased in 41 out of 50 (82%) of the gastric cancer tissues, when compared with normal stomach tissues, while no relationship was found between CA11 expression and various clinicopathological characteristics including histological type, depth of invasion, lymph node metastasis, and clinical stage. Immunohistochemical analysis with anti CA11 antibody showed that CA11-positive staining was observed in the surface regions of normal gastric epithelium, but was found faintly or not at all in cancer tissues. CA11 transfected MKN28 cells also displayed a marked decrease in the number of colony formations when compared to double normal controls. These findings suggest that the loss of CA11 expression in gastric tissues may play an important role in gastric carcinogenesis.

Adenocarcinoma↗
PubMed2000

Genetic analysis of thiopurine methyltransferase polymorphism in a Japanese population.

Thiopurine methyltransferase (TPMT) catalyses the S-methylation of thiopurine drugs such as 6-mercaptopurine, 6-thioguanine, and azathiopurine. Several mutations in the TPMT gene have been identified which correlate with a low activity phenotype. The molecular basis for the genetic polymorphism of TPMT has been established for European Caucasians, African-Americans, Southwest Asians and Chinese, but it remains to be elucidated in Japanese populations. The frequency of the four allelic variants of the TPMT gene, TPMT*2 (G238C), TPMT*3A (G460A and A719G), TPMT*3B (G460A) and TPMT*3C (A719G) were determined in Japanese samples (n=192) using polymerase chain reaction (PCR)-RFLP and allele-specific PCR-based assays. TPMT*3C was found in 0.8% of the samples (three heterozygotes). The TPMT*2, TPMT*3A and TPMT*3B alleles were not detected in any of the samples analyzed. This study provides the first analysis of TPMT mutant allele frequency in a sample of Japanese population and indicates that TPMT*3C is the most common allele in Japanese subjects.

Alleles↗
PubMed2000

Adenovirus-mediated in utero gene transfer in mice and guinea pigs: tissue distribution of recombinant adenovirus determined by quantitative TaqMan-polymerase chain reaction assay.

Fetal somatic cell gene therapy could become an attractive solution for some congenital genetic diseases or the disorders which manifest themselves during the fetal period. We performed adenovirus-mediated gene transfer to mice and guinea pig fetuses in utero and evaluated the efficiency of gene transfer by histochemical analysis and a quantitative TaqMan-polymerase chain reaction (TaqMan-PCR) assay. We first injected a replication-deficient recombinant adenovirus containing the Escherichia coli LacZ gene driven by a CAG promoter (AxCALacZ) into pregnant mice through the amniotic space, placenta, or intraperitoneal space of the fetus. Histochemical analysis showed limited transgene expression in fetal tissues. We then administered AxCALacZ to guinea pig fetuses in the late stage of pregnancy through the umbilical vein. The highest beta-galactosidase expression was observed in liver followed by moderate expression in heart, spleen, and adrenal gland. The transgene expression was also present in kidney, intestine, and placenta to a lesser degree. No positively stained cells were observed in lung, muscle, or pancreas except in the vascular endothelium of these organs. Quantitative measurement of recombinant adenoviral DNA by the TaqMan-PCR assay showed that the vast majority of the injected viruses was present in liver. The current study indicated that adenovirus-mediated gene transfer into guinea pig fetus through the umbilical vein is feasible and results in efficient transgene expression in fetal tissues. The experimental procedures using pregnant guinea pigs might serve as a good experimental model for in utero gene transfer. Since our TaqMan-PCR assay detects the LacZ gene, one of the most widely used reporter genes, it may be generally applicable to adenovirus quantification in various gene transfer experiments.

Adenoviridae↗
PubMed2000

Haplotype analysis suggests that the two predominant mutations in Japanese patients with holocarboxylase synthetase deficiency are founder mutations.

Holocarboxylase synthetase (HCS) deficiency is a rare autosomal recessive disorder of biotin metabolism. Including three new Japanese patients we diagnosed in this study, ten Japanese families have, so far, been accumulated. In these families, the mutations 237Leu > Pro (seven alleles) and 1067delG (five alleles) were predominant; 508Arg > Trp and 55(Val > Met mutations were identified in three families in the heterozygous form and in one patient in the homozygous form, respectively. To determine the origin of these mutations, we identified new polymorphic microsatellite markers in the HCS gene and analyzed the haplotypes of the patients. All the 237Leu > Pro and the 1067delG alleles were associated with haplotype 2-2. This finding is consistent with the notion that these mutations are founder mutations in the Japanese population. Three Japanese 508Arg > Trp alleles were associated with several haplotypes, including 2-3 and 1-4. The haplotype of a Taiwanese patient homozygous for the 508Arg > Trp mutation was 2-3/2-3. The haplotype of one Japanese patient homozygous for the 550Val > Met mutation was 1-4/1-4, whereas that of a Jewish patient with the same homozygous mutation was 2-3/2-3. Both mutations were associated with at least two haplotypes and were found in several ethnic groups. The changes 508Arg > Trp and 550Val > Met occurred at CpG dinucleotide. The data suggest that these two mutations represent a mutational hot-spot.

Biotin↗
PubMed2000

Total gastrectomy with dissection of lymph nodes along the splenic artery: a pancreas-preserving method.

BACKGROUND: In Japan, the tail and body of the pancreas are generally removed for dissection of lymph nodes along the splenic artery. A new pancreas-preserving method was developed to decrease the postoperative complications due to pancreatic resection. PATIENTS AND METHODS: Between 1981 and 1989, 110 patients were registered in a randomized controlled trial, which included total gastrectomy plus dissection of lymph node along the splenic artery, either with (55 patients: Group A) or without (55: Group B) pancreas tail resection. In Group B, the splenic artery and spleen were removed and the pancreas was preserved. There were no significant differences between the two groups in terms of sex, age, location, microscopic classification, or disease stage. The postoperative complications and survival rates were compared between the two groups. RESULTS: The average number of dissected nodes along the splenic artery was 4.6 and 4.1 for Groups A and B, respectively. The amounts of blood loss during the operation were 994 ml and 904 ml for groups A and B, respectively. Anastomosis failure and/or pancreatic fistula occurred in nine patients in Group A (16%) and seven in Group B (13%). One year after the operation, a glucose tolerance test showed diabetes in 6% and impaired glucose tolerance in 33% of patients in group A, while these findings were normal in group B. The 5-year survival rates were 80% and 76.7% for groups A and B, respectively. CONCLUSIONS: The pancreas-preserving method described here was superior to the more common pancreas resecting method with regard to surgical risk and postoperative glucose tolerance.

Adult↗
PubMed2000

In vivo adenovirus-mediated endothelial nitric oxide synthase gene transfer ameliorates lung allograft ischemia-reperfusion injury.

OBJECTIVE: Nitric oxide regulates vascular tone, inhibits platelet aggregation, and inhibits leukocyte adhesion, all of which are important modulators of ischemia-reperfusion injury. This study aimed to determine the effects of endothelial constitutive nitric oxide synthase gene transfer on ischemia-reperfusion injury in a rat lung transplant model. METHODS: In group I, donor animals were injected intravenously with 5 x 10(9) pfu of adenovirus-encoding endothelial constitutive nitric oxide synthase. Groups II and III served as controls, whereby donor animals were injected with either 5 x 10(9) pfu of adenovirus encoding beta-galactosidase or saline solution, respectively. Twenty-four hours after injection, left lungs were harvested and preserved for 18 hours at 4 degrees C, then implanted into isogeneic recipients, which were put to death 24 hours later. Recombinant endothelial constitutive nitric oxide synthase gene expression was evaluated by Western blotting and immunohistochemistry. Lung grafts were assessed by measuring arterial oxygenation, myeloperoxidase activity, and wet/dry weight ratios. RESULTS: Western blotting confirmed the overexpression of endothelial constitutive nitric oxide synthase in lungs so transfected compared with controls. Twenty-four hours after reperfusion, mean arterial oxygenation was significantly improved in group I compared with group II and III controls (189.4 +/- 47.1 mm Hg vs 71.7 +/- 8.9 mm Hg and 67.8 +/- 12.2 mm Hg, P =.02, P =.01, respectively). Myeloperoxidase activity, a reflection of tissue neutrophil sequestration, was also significantly reduced in group I compared with groups II and III (0.136 +/- 0.038 DeltaOD/mg/min vs 0. 587 +/- 0.077 and 0.489 +/- 0.126 DeltaOD/mg/min, P =.001, P =.01, respectively). CONCLUSION: Adenovirus-mediated gene transfer with endothelial constitutive nitric oxide synthase ameliorates ischemia-reperfusion injury as manifested by significantly improved oxygenation and decreased neutrophil sequestration in transplanted lung isografts. Endothelial constitutive nitric oxide synthase gene transfer may reduce acute lung dysfunction after lung transplantation.

Adenoviridae↗
PubMed2000

Synchronous esophageal and renal cell carcinoma.

Multiple cancer associated with esophageal cancer is not uncommon; however, synchronous esophageal and renal cell carcinoma is very rare. Only three cases have been reported to date, and one of these patients was treated in our institution. We have since successfully treated another patient. Here, we report the two cases treated in our institution. In the first case, esophagectomy, nephrectomy, and reconstruction using a gastric tube were carried out in one stage. Post-operative renal function was temporarily impaired by the complications of anastomotic leakage and pyothorax but no hemodialysis was needed. In the second case, as the patient had undergone distal gastrectomy because of gastric cancer, we chose a two-stage operation, i.e. esophagectomy and nephrectomy as the first stage, followed by reconstruction using a colon substitute after 4 weeks, resulting in only slight renal dysfunction. Patients 1 and 2 are alive and well 7 years and 2 years after the operations respectively.

Aged↗
PubMed2000

Glycogen storage disease type Ib without neutropenia.

We report 2 patients with atypical glycogen storage disease type Ib without neutropenia or infectious complications. Neither patient was deficient in hepatic glucose-6-phosphatase activities in microsome-disrupted homogenates; both had mutations in the glucose-6-phosphate transporter gene, suggesting an allelic variant of glycogen storage disease type Ib.

Adult↗
PubMed2000

Chemotactic activity for polymorphonuclear leukocytes: meconium versus meconium-stained amniotic fluid.

PROBLEM: Our previous study indicated that meconium-stained amniotic fluid (turbid AF) possessed a potent chemotactic activity for leukocytes, which may be dependent on interleukin-8. It is not known, however, whether meconium itself possesses this chemotactic activity. METHOD OF STUDY: Meconium samples were collected from mature neonates with and without turbid AF. A 5% meconium suspension in phosphate buffered saline was prepared and measured for its chemotactic activity for leukocytes using the blind well chamber technique. Concentrations of IL-8, TNFalpha and IL-1beta were also measured with ELISA. RESULTS: The number of leukocytes that migrated to the meconium suspension (35 +/- 27) was comparable with that of the clear AF (31 +/- 37), but was significantly lower than that of the turbid AF (184 +/- 62, P < 0.0001). The meconium suspension contained much lower levels of IL-8, TNFalpha and IL-1beta than the turbid AF. CONCLUSIONS: Meconium itself exhibits a lower chemotactic activity for polymorphonuclear leukocytes than turbid AF in vitro. The leukocyte chemotactic activity of turbid AF does not originate from meconium itself.

Amniotic Fluid↗
PubMed2000

Rapid detection of CYP2C18 genotypes by real-time fluorescence polymerase chain reaction.

In man, CYP2C19, a liver enzyme, plays an important role in the metabolism of several drugs. Mutation of the CYP2C19 gene results in a poor metaboliser phenotype. S-Mephenytoin hydroxylation genetic polymorphism is due to two mutations of the CYP2C19 gene, namely CYP2C19*2, located in exon 5, and CYP2C19*3, located in exon 4. CYP2C18 is also polymorphically expressed. The mutant alleles of this enzyme are CYP2C18m1, located in exon 2 and CYP2C18m2, located in the 5'-flanking region. We have developed an allele-specific TaqMan polymerase chain reaction (PCR) assay with which to detect CYP2C18 mutant alleles. This assay combines hybridization of the TaqMan probe and allele-specific amplification primers to the target DNA. The TaqMan probe is labelled with 6-carboxyfluorescein at the 5' end and 6-carboxytetramethylrhodamine together with a phosphate at the 3' end. Genotypes are separated according to the different threshold cycles of the wild type and mutant primers. We applied this procedure to DNA extracted from the blood or saliva of 144 healthy Japanese volunteers. The wt/wt, wt/m1, wt/m2, m1/m1, m1/m2 and m2/m2 genotypes of the CYP2C18 alleles detected by the assay were consistent with the results obtained from restriction enzyme cleavage. In accordance with a previous report, the genotypes of CYP2C18m1 and CYP2C18m2 coincided with those of CYP2C19*3 and CYP2C19*2, respectively. Therefore, detection of CYP2C18 mutant alleles also allows that of CYP2C19 mutant alleles. Among 19 poor metabolisers, eight showed the homozygous CYP2C19*2/CYP2C19*2, two the homozygous CYP2C19*3/CYP2C19*3 and nine the compound heterozygous CYP2C19*2/CYP2C19*3 genotype. We found the allele-specific TaqMan PCR assay rapid, simple and cost-effective, as well as suitable for high-throughput applications in a routine laboratory. This assay allows the fast and reliable detection of inherited disorders that might influence diagnosis and treatment.

Aryl Hydrocarbon Hydroxylases↗
PubMed2000

Detection assay of rare variants of the thiopurine methyltransferase gene by PCR-RFLP using a mismatch primer in a Japanese population.

Thiopurine methyltransferase (TPMT) catalyzes the metabolism of important drugs such as 6-mercaptopurine, 6-thioguanine, and azathioprine. The identification and frequency distributions of several variant TPMT alleles (TPMT*2--*8) have been described recently in many ethnic groups. We have recently demonstrated that TPMT*3C is the most common allele in Japanese subjects; however, it remains to be elucidated whether TPMT*4--*8 variants also exist in Japanese subjects. To detect polymorphisms in the TPMT gene (TPMT*4--*8), we have developed a mismatch polymerase chain reaction and restriction fragment length polymorphism method and conducted a population study of Japanese subjects. Genotyping of these variant forms was carried out in 192 Japanese healthy volunteers. The TPMT*4, TPMT*5, TPMT*6, TPMT*7, and TPMT*8 variants were not detected in any of the samples analyzed. This study provides the first analysis of the TPMT*4--*8 variants in a sample of the Japanese population and indicates that TPMT*4--*8 variants do not occur or are rare alleles in this population.

Alleles↗
PubMed2000

High throughput detection of drug-metabolizing enzyme polymorphisms by allele-specific fluorogenic 5' nuclease chain reaction assay.

We have developed an allele-specific fluorogenic 5' nuclease chain reaction assay for detecting polymorphisms in the following human drug-metabolizing enzyme genes: CYP2C9 (CYP2C9*2 and *3), CYP2C19 (CYP2C19*2 and *3), CYP2D6 (CYP2D6*4, *10, *14, *18, and *21(C8)), N-acetyltransferase 2 (NAT2*5B, *6A, and *7B), thiopurine methyltransferase (TPMT*3C), and aldehyde dehydrogenase2 (ALDH2*2). This method is a marriage of two emerging technologies, the use of allele-specific amplification primers for target DNA and hybridization of the TaqMan probe. The TaqMan probe is labeled with both a fluorescent reporter dye and a quencher dye. Genotypes are separated according to the different threshold cycles of the wild-type and mutant primers. All assays are performed using a single thermocycling protocol. This genotyping method is rapid and highly sensitive and yields a high throughput. It could be applied toward automated large-scale genotyping.

Aldehyde Dehydrogenase↗
PubMed2000

Administration of interferon-alpha during pregnancy: effects on fetus.

Interferon-alpha (IF alpha) is used for the treatment of myeloproliferative diseases and chronic viral illnesses. Because the agent has antiproliferative activity, its effects on a fetus are a concern. We encountered a 40-year-old Japanese woman who inadvertently received IF alpha during pregnancy for the treatment of HCV hepatitis. The patient received 5 million units of IF alpha 2 to 4 times per week (total dose of 315 million units) between 13 and 33 weeks gestation. The patient delivered a normally formed healthy male infant, weighing 2,252 g at 37 weeks of gestation. The infant at 20-month-old exhibited normal growth and neurological development when last examined. Literatures were reviewed to determine the effects of IF alpha on the fetus. There have been 27 infants born to 26 mothers, including the present case, who were exposed to IF alpha in utero. Six women (23%) were administered IF alpha inadvertently during pregnancy. Four women (15%) gave birth prematurely. Although 6 infants (22%) were affected by intrauterine growth retardation (IUGR), there were no IF alpha-related malformed infants. These results suggested that an inadvertent administration of IF alpha during pregnancy may occur, but in that case IF alpha may not induce congenital malformations. These findings may encourage such women to continue pregnancy.

Adult↗